Global Warming

Generally , the global warming refers to an average increase in the Earth ‘s temperature , which in turn causes changes in climate . Some scientists like to mention the global warming as green house effect “Global warming has reached a level such that we can ascribe with a high degree of confidence a relationship between the green house effect and the observed warming (Paterson , 1996 ,

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On of the major causes of global warming is the global climate that is changing because of the build-up in the atmosphere of carbon [banner_entry_middle]

dioxide (CO2 , methane , nitrous oxide (N20 , and the CFC (powerful green house gases as well as destroyers of stratospheric ozone (O ‘Carrol , 2002 Another reason of the global warming is green house effect . About 30 gases produced by human activity have been identified as contributing to the green house effect . Emission of Co2 and other harmful gases from the man made factories and industries affects the ozone layer of the earth and contribute to the global warming

However , the problem of global warming imposes even greater challenges on the populations of polar bears . Polar bears inhabiting southern areas of the Arctic Circle are stranded each summer as the melting of ice packs starts . Moreover , being separated from their principal prey of ringed seals , the bears endure a summer-long last until the ice returns in November . According to explanations given by Arctic ecosystems expert Derocher , The climate predictions coming out are showing massive changes in sea-ice distribution .You don ‘t have to be a polar scientist to see that if you take away all the sea ice you don ‘t have polar bears anymore (Cristol , 2003 ,

.6 . Indeed , over the last 35 years , Arctic ice has thinned from an average of 3 .1 meters to 1 .8 meters (Cristol As a consequence of the climatic shifts , polar bears are eating less thus building up less fat reserves and have fewer chances to survive during hard seasons . Moreover , it diminished cubs ‘ birth rate as well as their survival rate because they do not have enough fat too

According to Cristol , some scientists have even predicted the Arctic Ocean could be entirely ice-free by 2050 (Cristol , 2003 ,

.7 . If these global warming forecasts are correct , they may be a harbinger of what is to come throughout the circumpolar region as the Earth ‘s climate continues to heat up . Long-term temperature increases will mean a diminished ice pack that , in turn , will affect the survival of ringed seals , polar bears , and other northern species in unknown ways . As always , that future depends on actions taken in the present